A city in northwestern Iran which has a major weaving tradition dating to the 15th century. It was at this time that weavers from Tabriz introduced the curvilinear designs to the courts at Istanbul. After a decline of a few hundred years, Tabriz began re-establishing its position in the mid 19th century as the market center for the export of Persian Rugs to the west. Tabriz weavers have a reputation of copying designs from other areas of Iran and therefore the best way to establish the true origin of a Tabriz is by examining the rug's structure. Tabriz rugs are double wefted, Turkish knot is dominant, warps and wefts are of cotton and are mostly undyed (at times however, wefts may be either pale blue or light gray). Many designs are used and include medallions, hunting patterns, prayer and pictorial rugs. Some superb silk Tabriz rugs were woven during the late 19th century.